OBJECTIVETo induce primary chronic myeloid leukemia (CML) cells into dendritic cells (DCs).

METHODSBone marrow mononuclear cells (MNCs) were isolated from 13 CML patients and peripheral blood MNCs from 5 healthy donors. The isolated MNCs were co-cultured with rhGM-CSF 1,000 U/ml, rhIL- 4,500 U/ml and TNF-alpha 50 U/ml for 10 days. The morphological features were observed by Wright's staining,inverted microscope and electron microscope. CD(80), CD(86), CD(83), CD(1a) and HLA-DR expression were assayed by flow cytometry, cytogenetic analysis was performed by fluorescence in-situ hybridization(FISH). The concentration of IL-12 was measured by ELISA and the function of antigen presenting was tested by mixed lymphocyte reaction (MLR).

RESULTAfter being cultured with cytokines, the typical dendritic appearance with delicate membrane projections was observed. The CD(80), CD(86), CD(83), CD(1a) and HLA-DR markers and capacity of stimulating allogeneic T cells were upregulated significantly. FISH confirmed that the DCs were generated from leukemic origin and CML DCs could secrete higher level of IL-12 than CML MNCs. There were no differences in morphology and immunophenotype expression between DCs derived from CML and those from normal individuals. However, DCs from CML patients displayed weaker activity than that of normal individuals when tested in MLR.

CONCLUSIONCML cells could be induced into leukemia-DCs by co-culture with cytokines.